The metallic cans for beverages, of steel or aluminum, have undergone important development because of the qualities they possess for the preservation and commercialization of the beverages they contain.
They have however certain drawbacks or faults which should be overcome.
The principal drawback of these cans is connected to the manner of opening them, namely the use of a detachable lid, or more recently, one that can be pushed in. This lid, which cannot be returned to its original position, does not permit consuming only a portion of the contents, then transporting the can partly empty at the risk of spilling the remaining contents. This is particularly disadvantageous in the course of a sport or recreational event, such as skiing, hiking, boating, etc. or during transport in a vehicle (automobile, motorcycle, motorbike, train, plane, etc.), such that the consumer is obliged to consume all at once all the contents of the can or to throw away the partially empty can, with in this latter case pollution of the environment by the contents.
Another drawback of metallic cans in that, although they are filled under very strict hygienic conditions, they are then subjected to atmospheric pollution in the course of their storage and transportation, such that the consumption of their contents is far from satisfactory as to the most elementary conditions of hygiene.
There was proposed in DE-U-7 723 959, a cover adapted to re-close a can with an opening that can be torn off, after partial consumption of the contents of this can. This cover has either a totally flat surface or a totally curved surface. Such a cover therefore permits re-closing the can when the latter is partially empty, but it is not possible to stack the cans for storage.
Moreover, this type of cover is proposed in the form in which it is connected to other covers by a tearing tongue. The presence of such a tearing tongue between at least two covers give rise to the risk of destruction of the cover upon their separation by tearing off and is not a very easy manipulation. A seller would have the tendency to separate the can from the cover when selling it, as often as selling it with the cover.
There is known from FR-A-1 365 481, covers for a receptacle, such as a jar of cream, of the type comprising a skirt extending to the periphery of a flat surface and permitting stacking said receptacles, the flat surface of the cover having on its upper surface a rib in relief which permits ensuring the centering of another receptacle disposed on said receptacle provided with the cover. However, such a cover does not permit a real stacking of the receptacles against particularly lateral displacement of the receptacles stacked on each other.